- John Manuel, Prince of Portugal, 1537-15541
- John V, King of Portugal, 1689-17501
- John, Duke of Burgundy, 1371-14191
- John, King of England, 1167-12161
- Kings and rulers--Duties1
- Kings and rulers--Genealogy1
- Knights of Malta1
- Knowledge, Theory of1
- Kufic1
- Kufr (Islam)1
- Kāfiyah (Ibn al-Ḥājib, ʻUthmān ibn ʻUmar)1
- Ladino poetry1
- Lafões, Pedro Henrique de Bragança, Duque de, 1718-17611
- Lang, Matthäus, 1468-15401
- Language and languages1
- Latin language--Grammar1
- Latin language--Study and teaching1
- Latin language--Style1
- Latin poetry1
- Laudatory poetry1